#include<iostream>
using namespace std;
int r,c;
const int N = 110;
int a[N][N];
int f[N][N];
int dx[]={0,0,-1,1};
int dy[]={-1,1,0,0};
int dfs(int i,int j)
{
	if(f[i][j]) return f[i][j];
	int len = 1;
	for(int k = 0; k < 4; k++)
	{
		int x = i + dx[k],y = j + dy[k];
		if(x < 1 || x > r || y < 1 || y >r) continue;
		if(a[i][j] <= a[x][y]) continue;
		len = max(len,dfs(x,y) + 1);
	}
	return f[i][j] = len;
	
}
int main()
{
	cin >> r >> c;
	for(int i = 1; i <= r; i++)
	{
		for(int j = 1; j <= c; j++)
		{
			cin >> a[i][j];
		}
	}
	
	int ret = 1;
	for(int i = 1; i <= r; i++)
	{
		for(int j = 1; j <= c; j++)
		{
			ret = max(ret,dfs(i,j));
		}
	}
	cout << ret;
	return 0;
 } 
